Manifold heater



Dec. 8, 1942. J HUBER 2,304,254

MANIFOLD HEATER Filed July 3; 1940 INVENTOR. JOHN s. VHU BER Patented Dec. 8, 1942 MANIFOLD HEATER I John S Huber; South Milwaukee, Wis., assignor to Nash-Kelvinator Corporation, Kenosha, Wis, a corporation ofMaryland' 1 7 1 Application 1111 3, 1940, Serial No. 343,773

8 Claims.

This invention relates to manifold heaters and has particular reference to means for controlling the temperature of the fuel mixture in an intake manifold cast in an internal combustion engine.

It is an object of this invention to provide a manifold which will be properly heated at all times.

It is another object of: this invention to provide a heater passage in the" block of an internal. combustion engine for maintaining a: suitablev temperature in the intake manifol v It is another object of this invention to provide-means for heating an-intakemanifold which means will maintain. a constantly suitable temperature in the manifold-without controlsor moving parts. f

It is another object of this invention to provide an intake manifold which is subject to the combined action. of exhaust gases and cooling. water in such a manner as to maintain a constantly suitable temperature.

Other objects and advantages of this invention will be apparent from a considerationofe the following description and claims and the attached drawing of which there is one sheet and. in which- V Figure 1 represents a front elevation of. the upper portion of an internal combustion engine of the L-head type;

Figure 2 represents a vertical sectional view taken along a plane indicated by the line 2 -2. in Figure 1 and looking inthe direction of the arrows;

Figure 3 represents a transverse sectional view taken along a plane indicated by the broken line 3-3 in Figure 2 and looking in the direction of the arrows;

Figure 4 represents a transverse sectional view taken along a plane indicated by the line 44 in Figure 2 and looking in the direction of the arrows.

It is a well established fact that better carbu retion and combustion in an internal combustion engine is obtained by maintaining the fuel mixture at the proper temperature which. is usually higher than the temperature of the'air surrounding the intake manifold and carburetor. It is also well established that too high a temperature will cause the fuel mixture. to-explode too soon in the engine and is generally detrimental to the :2

operation of the engine. .The need for heat in' the intake manifold is particularly noticeable when the engine is first started after being allowed. to

, be cooled for some time. Inthe past it has been the practice to conduct exhaust gases to some operating. limits by constructing the chamber under the intake manifold in such a manner that the'greater portion of the exhaust gases will not enterthe chamber when the engine is operating at high speed. The temperature of the intake manifold. is further controllediby subjectingthe' intake manifold and the heater. chamber to the action: of the, cooling water inthe engine,.thusat low speeds, as are encountered. in starting an en-' gine, a. greater portion of the exhaust gases remain in the heater chamber for a greater length of time and. there is less circulation ofcooling water around the chamber, while .at high speed a greater proportionof the exhaust gases pass directlyv out of the engine without afiecting the intake manifold and both the heater chamber and. intake manifold. are subjected to a more vigorous circulation of the coolingjwater. The above heat regulating system is accomplished Without controls or movablev dampers by an arrangement of the intake manifold and exhaust passages with respect to the cooling jacket of the engine, an example of which. will now be more particularly described.

Illutrated in. the drawing is. an internal combustion engine generally indicated. at Ill-having ablock l2 and a head I4. The. head I4 is secured to the block 12 by the .usual head bolts l6 and carries the usual spark. plugs l8 and a down draft carburetor 20. The block l2 carriesalongtheside thereof a tubular exhaust manifold ZZQsecured to the block by a series of clips 24 andbolt 26. The usual head gasket 28 is providedbetween the head I M and block l2.

Formed. along one. side of the block. I2. is. an overhanging. portion 30 within which is cast a longitudinally extending intake manifold 32 which is open along the top surface of. the block. Carburetor 20- discharges into the manifold, 32 through port 33 formed in the head l t... From the intake manifold. 32, ports 34 openinto intake passages 36 (see Figure 4) which may be siamesed to accommodate two cylinders. and whichare controlled by intake valves 38 to admit the-fuel mixture to combustion chambers 40 formed on the under surface of the head I4.

Between the intake passages 36, exhaust passages 42, controlled by exhaust valves 44, extend downwardly from the combustion chamber 40 and pass out through the overhanging portion immediately underneath the intake manifold 32. The exhaust pipe 22 is provided with apertures 46 which connect with the passages 42 to allow the exhaust gases to enter the exhaust pipe. It is to be understood that the exhaust passages 42 each. connect to one or two combustion chambers 40,

and that several of the passage are provid d as shown in Figure 2 r Between the several passages '42 and'i directly underneath the intake manifold 32 is formed'a the rest of the block and require no extra machining over a block without the heater chamber.

P .Theheat control is entirely automatic and has n'oimovin'gpartor. thermostat to become out of longitudinally extending chamber 48 which connects the several exhaust passages 42.

there is direct heat transfer bewe'e'n'the manifold andchamber. Q. Q

The space between the intake passages 36 and exhaust passages 42 is surrounded by cooling water space 50 which is in communication with the water jacket 52 around the'cylinder wall 54'. Particular attention is called to the fact that the cooling water space. 5Uextends completely along the under side and ends of the heater chamber 48 andalong the inside thereof between the exhaust passages '42.

The headcasting [4 which forms the combustion chambers 40 and closes the intake manifold .32-is 'alsoprovide'd with the familiar cooling ly across the heater passage: 48. When the engine is running at slow speed aswhen it is being started, the interval between the exhaust charges passing through the various passages 42 is relatively large and there is time for the exhaust gases to surge back and forth along the heater passage 48.and give up some of their heat to the common wall between the heater passageand the intake manifold. At high speeds notfonly will the charges of exhaust gas come morerapidly due to the higher speed of the pistons expelling them, butthey will come closer together sothat there will be very little differentialinpressure between one end of theheater passage 48 and the other. As a resultmost of the gases will pass directly across the heater chamber 48 into the exhaust pipe 22 without having much heating effect on the intake manifold. While theentire cross sectional area of the heater chamber- 48 is shown to be open to the exhaust passages 42, it might be desirable in some engines to restrict the. opening between the heater chamber and exhaust. passages.

. At high speeds, the differential in temperature between the walls of the heater'chamber 48 and the. water in the cooling'passages 50 becomes higher .so that a greater amount of the heat in the heater chamber 48 flows into" the cooling water than 'to the intake manifold 32. There is also a more rapid circulation of 'thewater It is to be noted that the bottom wall of the intake rn'anifold .32forms the top of this heater chamber 48 so that order. While the example illustrated is an engine of the L-head type, the same principle is readily adaptable to a valve-in-head engine and can be applied. to engines having intake manifolds mounted separatelyfr'om the block or head cast mes-1"". While {have describedm y inventionin some detail, I intend this description to be 'an example only and" not "limiting on my invention towhich I make'the following claims? A I 1. In combination with an internalcombustion engine having an, intake manifold, a heater chamber adjacent tosaid manifold, an exhaust passage opening from said engine into said heater chamber and] continued therebeyond across a short dimension-'of'said'heater chamber, an exhaust pipe connected to said passages on the oppositefsideof said; heater chamber from said engine, and aco oling water jacket formed around said intake, manifold and heater chamb I T ."T v 2. n combination fwith a internal: combus tion engine having an exhaust pipe an intake manifold in a wall of said engine, a heater chamber adjacent said intake manifold, exhaust passages in said engine extending'from said engine tosaid exhaust pipe-said heater chamber communicating with the exhaust passages intermediatethe ends-thereof through thesides of the:pas sages, and a water jacket formed around said intake manifold, heater chamber and a portionof each'of said exhaust passages.

3. In combination with an internal "combustion engine having an intake manifold, an elon- 'gated heater chamber adjacent 'to said manifold, exhaustpassages opening into said heater chamber and directed across a short dimension of said heaterchamber, a wall of said heater chamber defining ports opening" into anexhaustpipe, said ports being directly opposite said exhaust passages, and a cooling water jacket formed around said intake manifold and heater chamber. 4. In combination with an internal combustion engine having an elongated intake manifold cast therein, exhaust passages cast in said engine and extending from the cylinders thereof across a 'wallof said manifold, a heater chamber positioned' adjacent tosaid ma'ni'fold and communicating with said exhaust passages, saidexhaust passages extending beyond said heater chamber through a side wall of said engine, and a water jacket cast around said intake manifold. exhaust passages and heaterchambr.

5. In combinationwith an internal combus tionengine having an intake 'manifold castth'erein, an exhaust pipe, a heater chamber cast along one wall of said manifold, a plurality of exhaust passages cast in said engine, said exhaust passages intersecting said heater chamber at right angles and extending therebeyond'to said exhaust pipe, and a cooling water jacket cast around said intake manifold, heater chamber and exhaust passages.

6. In combination with an internal combustion engine having an intake manifold cast therein, a heater chamber east along one wall of said manifold, a plurality of exhaust passages cast in said engine and intersecting said heater chamber at right angles, said exhaust passages extending on each side of said heater chamber to the side of said engine and to the cylinders thereof, and a cooling water jacket cast around said manifold, heater chamber and exhaust; passages.

7. In combination with an internal combustion engine having an intake manifold, an exhaust system for said engine having parallel passages connected at several points, one of said parallel passages being adjacent said intake manifold, said last mentioned passage being positioned between the cylindersof said engine and the other of said passagesand a cooling water jacket formed around said intake manifold and the passage of said exhaust system adjacent said manifold.

8. In combination with an internal combustion engine having an intake manifold, a plurality of exhaust passages extending at right angles to said manifold, an exhaust manifold located at the ends of said exhaust passages, a heater chamber parallel with said exhaust manifold and intersecting said exhaust passages, said heater chamber being adjacent said intake manifold and between said exhaust manifold and the cylinders of said engine, and a cooling water jacket formed around said intake manifold, exhaust passages and heater chamber.

1 JOHN S. HUBER. 

